Silo for granulous material



J. BOUTARD SILO FOR GRANULOUS MATERIAL May 15, 1956 4- Sheets-Sheet 1Filed April 2, 1951 May 15, 1956 .1. BOUTARD 2,745,520

SILO FOR GRANULOUS MATERIAL Filed April 2, 1951 4 Sheets-Sheet 2 May 15,1956 J. BOUTARD SILO FOR GRANULOUS MATERIAL 4 Sheets-Sneeh 3 Filed April2, 1951 May 15, 1956 J. BOUTARD SILO FOR GRANULOUS MATERIAL 4Sheets-Sheet 4 Filed April 2, 1951 United States Patent SILO FORGRANULOUS MATERIAL Jacques Boutard, Pringy par Ponthierry, FranceApplication April 2, 1951, Serial No. 218,761

Claims priority, application France June 20, 1950 13 Claims. (Cl. 1893)It has been proposed in order to reduce the values of the stressesexerted on the walls of silos to give the the latter such a shape thatthey offer to the granulous material a series of elemental restingsurfaces which are inclined and superimposed upon one another with theinterposition of vertical surfaces, the sloping of these elementalsurfaces and their vertical dimensions being suchthat not only they maygive rise to the formation of natural crumbling banks as concerns eachof said loping resting surfaces but furthermore that the height of eachof said crumbling banks may be small enough, on the one hand, that theydo not give undue transversal dimensions to the silo and, on the otherhand, that they stiffen the walls of the silo and thus enable it tobetter withstand the radial thrusts exerted thereon.

It has been proposed to carry this general idea into practice by meansof structures of reinforced concrete but the construction of silos whenusing this building material is very expensive whether a circular or apolygonal shape is given to such silos. Moreover in such cases theconstruction of the walls with the sloping planes under con- I Anotherobject of the invention is to provide a silo in which the flowing of thegranulous material in the direction of the outlet of the same is veryeasy.

A further object of the invention is to provide a silo the walls ofwhich are very easy to build separately and can be premanufactured in aworkshop and can be easily transported to the place where the silo is tobe erected.

Another further object of the invention is to provide a silo which isvery easy to erect and which necessitates but small and cheapfoundations.

Still another object of the invention is a silo which can easily be madeairtight.

A further object of the invention is also to easily build very lightpolycellular silos on a small ground, practically all the surface of thelatter being used.

In order to realise the above said objects the present invention appliesthe hereabove recited principle to the construction of metallic silos bymaking the latter of premanufactured panels starting from metal sheets,plane or cylindrical, said sheets being corrugated by folding them insuch a manner that they are made to comprise sloping and verticalsurfaces, such as those which are mentioned above as used in silos ofreinforced concrete. To the lateral or side edges of these corrugatedsheets are welded flat bands of metal, such e. g. as fiat-billets. Byplacing several of such panels vertically side by side along the edgesof their flat-billets and by welding said edges onto one anice other acontinuous ring or cell member is formed which constitutes the firstlayer of the silo wall. On the other hand, by welding a thirdflat-billet on both other edges of each side flat-billet of twopremanufactured panels so joined together a caisson-beam is formed ateach joining line of two panels which contributes to stiffen the wholeof the said cell-member and constitutes a vertical supporting girder. 7

By forming in such a manner a series of cell-members, starting from aflat metal-sheet, one over the other and welding them to one anotherthrough the respective upper and lower edges of the said cell-memberssheets and abutting ends of flat-billets a polygonal silo of the desiredheight is thus raised.

By starting from a cylindrical metal-sheet generally cylindricalpremanufactured panels are formed when joining together a member of soformed panels side by side and one upon another in the hereaboveindicated manner, a complete cylindrical metallic silo having a circularbase, is formed.

Whilst it is preferable in such a construction to cut the side edges ofthe premanufactured panels along an angle of in relation to thetheoretical median plane of the said panels, when a polygonal silo iswanted, it is advantageous to cut the said side edges at an angle ofless than 90 when a cylindrical silo is wanted, in order to keep thepossibility of building a triangular beam at the contact line of twopanels.

The use of six panels of general plane shape possessing sidefiat-billets welded perpendicularly to the theoretical median surface ofthe panel makes it possible with flatbillets of the same width as thosewhich are welded on the edges of the said members to form amono-cellular silo constituted by an unique hexagonal cell or when usingmore than six panels to form a multi-cellular silo formed of a pluralityof cells joined side by side and in which one wall may be common to twoadjacent cells and in which the flat-billet which gives rise to theformation of the triangular beam may be the side flat-billet of a panelbelonging to two adjacent silo units.

The use of metal for such a structure oflers considerable advantages inthat it makes it possible to make in a workshop panels showing perfectlypredetermined shapes and which, since they are indeformable in thepresence of the stresses which are necessary for their conveyance andfor the construction of the whole of the silo, render it possible oneasy transport of the same from the workshop to the building yard, aneasy handling and an easy reciprocal setting in place of the panels bymeans of hoists of small power. No moulds are necessary and thescatfolds are minimized. Furthermore, owing to the considerablereduction of the stresses exerted on the sheets of the silo s walls themetal may be chosen of a much smaller thickness than in an ordinarymetallic silo. Either in the case of the walls proper or in the case ofthe supporting caisson-beams the distribution of the metal is definitelymore rational which explains the smaller weight of such a silo for anequal capacity of the same.

Owing to the reduced weight of the so formed silo it is sufiicient inorder to support it, to erect it on foundation bodies of a reducedpattern. Furthermore, the covering of any silo-cell so formed by meansof a metal sheet cap made of premanufactured members joined together andto the upper cell member of the silo, and also the adjunction to thelower part of the said silo-cell of a metallic hopper formed ofpremanufactured elements also joined through welding, give remarkableconstruction facilities. Furthermore by the welding together of all theparts of the silo it is possible to render it air-tight.

On the other hand, metal offers with respect to concrete the advantagesof tightness even along the junction lines or junction surfaces andsmaller rubbing coeflicient.

Consequently, the qualities of such a silo are due not only to thephysical and chemical properties of metal with respect to reinforcedconcrete but also to the possibility of premanufacturing and joiningtogether the panels by means of autogenous welding or arc welding orthrough any other convenient means, with formation'of stifiening andsupporting beams by using certain parts of the premanufactured partsthemselves of the panels.

Different kinds of silos built according to the invention and certaindetail arrangements and possible modifications are shown by way ofexample in the accompanying drawings.

In said drawings:

Fig. l is a perspective elevational view showing a wall member asobtained in a premanufacturing workshop.

Fig. 2 is a plan view of the said member.

Fig. 3 is a horizontal sectional view showing a portion of a hexagonalcell made with such members.

Fig. 4 is a horizontal sectional view, on a larger scale, showing theassembly of the sides of two wall members.

Fig. 5 is an elevational view showing a complete cell with a flatbottom.

Fig. 6 is a top view showing this cell.

Fig. 7 is a cross-sectional view showing a multi-cellular silocomprising hexagonal cells joined side by side with one another.

Fig. Sis a view, on a larger scale, showing an assembly knot of the wallmembers of such a silo.

Fig. 9 is an elevational view of the multi-cellular silo shown in Fig.7.

Fig. 10 is a plan view of a cylindrical silo.

According to Figs. 1 and 2 a panel or wall member of a silo is formed ofa thin metal sheet folded in order to include, once the panel is put inplace, vertical portions or parts such as 1 and portion or parts slopingin reverse directions such as 2 and 3.

The side edges of the .so folded sheets are joined to fiat billets orhands 4 and 5 by means of autogenous welding, the flat billets or bands4 being shown in chain dotted lines in order to cause the design of thefolded edge of the sheet to appear in said Figs. 1 and 2. A wall memberis thus formed which will be used in building a silo.

The design of the panel or wall member formed by the folding of theparts or portions 1, 2 and 3 of the sheets of the panels may also beestablished in such a manner that the sides of the same show declivitieswhich are greater than those of the natural crumbling slopes of thegranulous material to be stored in the silo. In such a case the panel iscompletely filled with pulverulent material and as concerns this part ofthe wall there is no longer a rubbing of the stored material against themetal of the wall member; but a rubbing of stored material on storedmaterial which leads to a considerable reduction of the rubbing stressesexerted on the walls, more particularly at the moment of the emptying ofthe silo.

For making a silo with a horizontal hexagonal section such as shown inFigs. 3, 4, 5 and 6 two panels of this kind are first Welded togetherwhile being orientated at 120 with respect to each other as shown inFigs. 3, 4 and 6 the welding being effected along the edges 6 of bothflat-billets or bands contacting side by side, and then anotherflat-billet 10 is welded along the two other edges 8 of bothflat-billets already welded at 6, which not only insures an indeformableconnection of both wall ele ments owing to the so formed triangulationbut gives also rise to the formation of a triangular caisson-beam 5, 5,10 (Figs. 3 and 4).

By welding six identical Wall panels one against the other along ahexagon a first cell ring is obtained. Then another panel issuperimposed to each panel of the said first cell-ring and the upper endedge of the flat-billets or bands 4, 5 of each panel of the first cellring is welded to the lower edge of the corresponding fiat-billets ofthe so added further panel and the vertical edges of the flat-billets ofeach the added panels are respectively welded together. The upper andlower edges of the sheets of the superimposed panels are then welded inthe same manner and a second cell-ring is thus formed, and so on up tothe upper part of the silo, the latter finally appearing as a hexagonalprism, an elevational view of which is shown in Fig. 5 and a horizontalsection of which is shown in Fig. 3 on an enlarged scale.

In order to cover the silo a pyramidal cap Showing a hexagonal section(Figs. 5 and 6) is welded on the upper part of the upper cell-ring, saidcap being provided with a filling opening 12, a hermetic access door 13and, as the case may be, a sound-indicator 14 intended for signalisingthe moment the silo is filled with the pulverulent material introducedtherein through opening 12.

In a like manner either a flat sheet bottom 15 as shown in Fig. 5 or ahopper 16 is welded onto the base of the lower cell-ring as shown inFig. 9.

The hexagonal shape of a so established silo-cell renders it very easyto join side by side a plurality of such cells for forming a cellularsilo such as shown in Figs. 7 and 9, the walls 17, 18, 19, 20, 21 and 22of the middle cell forming both a wall for said middle cell and a wallfor the cells surrounding the same, and the walls 23, 24, 25, 26, 27 and28 becoming common to the six cells which surround the middle cell. Thevertical tubular stiffening and supporting caisson-beams are formed ofthe flat-billets of the sides of the three panels 17, 18, 23 whichconverge to one and the same junction knot (Fig. 8) and are weldedtogether.

When a cylindrical silo is wanted it can be built of panels constructedas those shown on 1 and 2 but possessing a theoretical median surfacewhich is cylindrical. Such a silo is represented in plan view on Fig.10. Instead of being cut at an angle of the edges of said circularpanels are cut at an angle of, let us say, 60 (Fig. 10). Flat-billets 4aand 5a are welded on the lateral sides of the sheet 1a, 2a, 3a and aflat-billet 10a is welded onto the billets 4a, 5a. When giving to thesteel sheet a length corresponding to an angle of 60 at the center 16 ofa circumference it is possible to build a circular silo such as shown onFig. 10 by welding together six panels.

A silo made according to the invention is perfectly well adapted forbeing combined with receiving and cleaning stores, with emptying spouts,channels with worms, man-holes and other arrangements commonly used insilos.

What I claim is:

l. .A metallic silo formed of vertically superimposed and laterallyadjacent panels each of them comprising a horizontally corrugated metalsheet, a metal-band at each side of each metal sheet, each sheet beingwelded along each of the vertical lateral sinuous sides to faces of saidmetal-bands respectively, the breadth of each said metal-band beingdisposed at an angle with respect to the theoretical median surface ofthe said corrugated metal-sheet and the length of which substantiallycorresponds to the length of the lateral side of the said corrugatedmetal-sheet, the upper edge of the said corrugated metal-sheet lying inone and the same line as the lower edge of the corrugated metal-sheet ofthe upper adjacent panel and being welded thereto, two adjacent verticaledges of the metal-bands of two laterally adjacent panels being weldedtogether along their said edges and the upper end of each of saidmetal-bands being welded to the lower end of the corresponding metalband of the adjacent panel located above, and both so together weldedmetal-bands being welded along their respective other edges to therespective edges of a third metal-band with a hollow space existingbetween the three so welded metal-bands.

2. A metallic silo such as is claimed in claim l in the structure ofwhich are comprised panels the theoretical median surface of thecorrugated metal sheets of which is plane.

3. A metallic silo such as is claimed in claim 1 in the structure ofwhich are comprised panels the theoretical median surface of thecorrugated metal sheets of which is cylindrical.

4. A metallic silo such as is claimed in claim 1 in which the angle atwhich the breadth of the metal-band is disposed with respect to theheoretical median surface of the said metal sheet is 90.

5. A metallic silo such as is claimed in claim 1 in which the angle atwhich the breath of the metal band is disposed with respect to thetheoretical median surface of the said metal sheet is less than 90.

6. A metallic silo such as is claimed in claim 1 in which thecorrugations of the sheet metal forming the body of the panelsalternatively comprise a part which is parallel to the theoreticalmedian surface of the panel, a part which is inclined with respect tothe said surface, a further part which is again parallel to the saidsurface, a still further inclined part which is again inclined withrespect to the said median surface but in the reverse direction, saidsequence being repeated according to the desired length of said panels.

7. A metallic silo such as is claimed in claim 6 in which the slope ofthe inclined parts of the corrugated metalsheet corresponds to theinclination of the natural crumbling bank of the material to be stored.

S. A metallic silo such as is claimed in claim 6 in which the slope ofthe inclined parts of the corrugated metal-sheet is greater than theinclination of the natural crumbling bank of the material to be stored.

9. A metallic silo such as claimed in claim 1, in which substantiallytriangular metallic panels are welded by their base onto the upper edgeof the corrugated metal sheet of the upper panels and onto the upperends of the metal-bands of the said upper panels, the said substantially triangular metallic panels being welded together along theirconvergent sides.

10. A metallic silo comprising a central hexagonal silo-unit surroundedby six silo-units, each of the same central and surrounding silo-unitsbeing formed of vertical superimposed and laterally adjacent panels,each panel comprising a horizontal corrugated metal-sheet, acorresponding metal-band welded along each of the vertical lateralsinuous sides of said metal-sheet respectively, the breadth of each ofsaid metal-bands being disposed at 90 with respect to the theoreticalmedian surface of the corresponding corrugated metal sheet and thelength of which substantially corresponds to the length of the lateralside of the said corrugated metal sheet, the upper edge of the saidcorrugated metal-sheet laying in the same line as the lower edge of thecorrugated metalsheet of the upper adjacent panels and being weldedthereto, two adjacent vertical edges of the metal bands of two laterallyadjacent panels being welded together along their said edges and theupper end of each of the said metal bands being welded to the lower endof the corresponding metal-band of the adjacent panel located above, andboth so together welded metal-bands being welded along their respectiveother edges to the respective edges of a third unit metal-band with ahollow space existing between the three so welded metal-bands, each wallof the central Sil0-l1nit forming a wall of one of the surroundingsilo-units and each third metal-band of the central hexagonal silo-unitbeing one of the metalbands of one of the surrounding silo-units, eachof the corresponding hollow beams so formed being common to the centralsilo-unit and to two of the surrounding silounits.

11. In a metallic construction, more than two horizontally corrugatedvertical panels, the panels of each pair of two adjacent panels beingdisposed at an angle with respect to each other with the adjacentlateral edges thereof terminating respectively in a vertical plane,billets of substantially the same height as the corrugated panelscrossing and vertically secured fiatwise against the said edges of thecorrugations of the panels, the said billets convergently contactingwith each other along their adjacent edges and being secured to oneanother at their said edges, and a third vertical billet secured by andalong its two lateral edges to the opposite adjacent edges of the firstmentioned billets to form a hollow vertical beam at each convergent lineof adjacent panels.

12. In a metallic construction, two horizontally corrugated panels withthe corrugations extending to the edges thereof, each panel beingdisposed at an angle with respect to each other and with the side edgesterminating in vertical planes, fiat vertical billets contacting andsecured to the corrugated edges of the panels with the flat faces of thebillets closing the corrugations, said billets being secured to eachother along adjacent vertical edges in angular relation, and a verticalbillet having opposed vertical edges secured to the other vertical edgesof the first-mentioned billets to form a beam at the intersection of thepanels.

13. A metallic structure such as is claimed in claim 11 in which saidthird-mentioned billet closes the corrugations of another panel.

References Cited in the file of this patent UNITED STATES PATENTS521,951 Fallis June 26, 1894 1,605,513 Connery Nov. 2, 1926 1,842,735Spence Jan. 26, 1932 1,902,546 Ditchfield Mar. 21, 1933 2,226,681Willoughby Dec. 31, 1940 FOREIGN PATENTS 347,159 Germany Jan. 16, 1922356,493 Germany July 25, 1922

